Improvement in lifting-jacks



R. WHITTEMBRE.

Lifting-Jacks.

Patented Dec. 8, 1874.

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UNITED STATES PATENT ()FFIGE.

JOHN R. WHITTEMORE, OF GHICOPEE FALLS, MASSACHUSETTS.

IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 157,663, dated December 8, 1874; application filed May 18, 1874.

To all whom it may concern:

Be it known that I, JOHN R. WHITTEMORE, of Ohicopee Falls, Hampden county, Massachusetts, have invented certain new and useful Improvements in Lifting-Jacks; and do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings making a part of this specification, in which Figure 1 represents a side view with one side of the standard broken away at the top. Fig. 2 represents a front view, and Fig.3 a view of the catch which holds the lever in place. a

My invention relates to that class of lif ing-jacks in which a notched lifter is moved up and down upon a standard; and the nature of my invention consists in a notched lifter provided with vertical grooves on its sides, into-Which grooves fit flanged studs, which are secured to the front of the standard,the said lifter being provided with a rackbar, into which works the segmental end of a lever, all as more fully hereinafter set forth.

A represents a standard, rested upon a base,

' and having an open mortise at the top, into which is pivoted a lever, 0, having a segment at its end provided with cog-teeth. Upon the front of the standard are four flanged studs, F F F F, which are secured apart from each other by the screws G. B represents the lifter, which is inclined rearward at the upper part, and having notches b in stair-step form, so

that the top thereof extends over the top of.

the standard, while the lower part of the same rests against the front of the standard. The

straight portion of this lifter has a groove, H, on each side, and into these grooves the flanges on the studs F enter to hold it to the standard and allow it to be moved freely up or down.

lever against the same. The lit'teris perfectly guided in its up and-down movements by means of the grooves therein and the flanged studs.

Whenever itis necessary to remove the lifter it is only necessary to loosen two of the flanged studs on the same side, turn them on the screws,

and lift out the lifter B from the two nnloosened studs.

I do not claim a lifting iack in which an inclined notched lifter slides on a standard, and is operated by means of a segment acting upon a swinging rack-bar on the exterior of the lifter, as I am aware that such is now new.

What I claim is-- The combination, with the standard A, of the flanged studs F F and the lifter B, having vertical grooves H on its sides, all substantially as set forth.

JOHN R. WHITTEMORE. [L. 8.]

Witnesses:

I. W. SMITH, A. It. MARTIN. 

